Finally i had time to go and make this happen. Basically all it is is a BMS downpipe with the split cut off and then mated to a 3 inch pipe all the way back to the Custom muffler. I'm proud to say i'm the first one to do this on a 335i!. One would think that this exhaust would be really loud but it is actaully the tamest exhaust i've ever heard (the muffler is very packed). For it being fully catless, it seems like its not even as loud as my old setup (berk dp/stock exhaust). It does have a unique sound to it though.
Here are two really short videos of how it looks/sounds. I will be updating this thread with a better video when i have the time.

Cool idea, but you really are not benefiting any by getting rid of the split. The split is by no means in one bit restrictive. I highly doubt there was any gain from doing this modification over leaving the split there.

Cool idea, but you really are not benefiting any by getting rid of the split. The split is by no means in one bit restrictive. I highly doubt there was any gain from doing this modification over leaving the split there.

I doubt there was any major benefits from doing this too but i also do know this cost me a lot less than getting another aftermarket exhaust, it's something different/ unique, it made more sense for the dp not to have a split into two midpipes for a single turbo, it shaved a good amount of weight off of my car, and less back pressure.

I doubt there was any major benefits from doing this too but i also do know this cost me a lot less than getting another aftermarket exhaust, it's something different/ unique, it made more sense for the dp not to have a split into two midpipes for a single turbo, it shaved a good amount of weight off of my car, and less back pressure.

Those are all benefits to me...

Im sure gains are better, the split exhaust on our single turbo is useless.

I doubt there was any major benefits from doing this too but i also do know this cost me a lot less than getting another aftermarket exhaust, it's something different/ unique, it made more sense for the dp not to have a split into two midpipes for a single turbo, it shaved a good amount of weight off of my car, and less back pressure.

I agree the cost for a catback vs doing what you did I am sure is a huge difference. My point is running an aftermarket catback with a catless DP w/the split vs. your setup w/o the split there would be no difference in performance (some think there is) You basically made an AMS catback for your car, but for much cheaper. The only real benefit here is the cost is cheaper vs. purchasing a catback.

I tried telling you that muffler was quiet and made power. No one believed me.

magnaflowaflow haha

Yah the muffler is very quiet!! Magnaflowaflow is the shit haha. Adan tried making the piping as free flowing as possible with the least amount of bends. He did an awesome job. It's super quiet inside the cabin and when u get on it it sounds awesome. I have another video I'll upload tonight. It is actually very deep.